/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.dolphinscheduler.alert.service;

/**
 * The interface responsible for consuming event from upstream, e.g {@link EventPendingQueue}.
 *
 * @param <T> the type of event
 */
public interface EventLoop<T> {

    /**
     * Start the event loop, once the event loop is started, it will keep consuming event from upstream.
     */
    void start();

    /**
     * Handle the given event.
     */
    void handleEvent(T event);

    /**
     * Get the count of handling event.
     */
    int getHandlingEventCount();

    /**
     * Shutdown the event loop, once the event loop is shutdown, it will stop consuming event from upstream.
     */
    void shutdown();

}
